The present invention relates to a plasma display panel (PDP), being flat and capable of displaying a color image, whose screen size can be made to be large, and which is used such as for a personal computer (PC), a work station, and a wall TV set, and in which its luminance becomes higher and its power consumption is reduced.
Conventionally, a surface discharge type PDP has been used. This conventional PDP provides a group of many pairs of sustaining electrodes covered with a dielectric layer on a first glass substrate. And a gas is filled in a space between the first glass substrate and a second glass substrate facing the first glass substrate, and a discharge is generated by applying voltages to these pairs of sustaining electrodes, and ultraviolet light is obtained. The obtained ultraviolet light is irradiated to a fluorescent material and visible rays are obtained. FIG. 1 is a plane view and a sectional view showing a structure of a first conventional PDP. FIG. 2 is a perspective view showing the structure of the first conventional PDP. And FIG. 3 is a plane view and a sectional view showing a structure of a second conventional PDP. As shown in FIGS. 1 to 3, a pair of sustaining electrodes 11 is formed on a first glass substrate 10 in a first substrate 1 for a unit discharge cell 300, and the pair of sustaining electrodes 11 is covered with a dielectric layer 12 made of low-melting glass. At this time, the thickness of the dielectric layer 12 on the pair of sustaining electrodes 11 becomes nearly uniform.
In a case that a structure, in which the thickness of the dielectric layer 12 on the pair of sustaining electrodes 11 is nearly uniform, is used, when the thickness of the dielectric layer 12 is made to be large, the luminance efficacy becomes high. However, the discharge sustaining voltage is increased. On the contrary, when the thickness of the dielectric layer 12 is made to be small, the discharge sustaining voltage can be made to be low, but the luminance efficacy becomes low.
In order to avoid the problem mentioned above, a structure is proposed. FIG. 4 is a sectional view showing a structure of a first substrate 1 of a third conventional PDP. As shown in FIG. 4, the thickness of the dielectric layer 12 is not uniform at a unit discharge cell. However, in this structure, the thickness of the dielectric layer 12 must be formed precisely in the whole unit discharge cells of the PDP, and the thickness of the dielectric layer 12 is liable to be uneven. Consequently, this affects the characteristics of the PDP, and this structure makes a high quality PDP difficult.
It is therefore an object of the present invention to provide a PDP, in which a high quality image is displayed by making its luminance and its luminance efficacy high and also its power consumption is reduced.
According to a first aspect of the present invention, for achieving the object mentioned above, there is provided a PDP. The PDP provides a group of plural pairs of sustaining electrodes covered with a dielectric layer on a first glass substrate, by placing a discharge gap between the pair of sustaining electrodes, and a gas being filled up between the first glass substrate and a second glass substrate facing the first glass substrate. And an image is displayed on the PDP by irradiating ultraviolet light, which is obtained by making the group of plural pairs of the sustaining electrodes on the first glass substrate discharge by applying voltages to the group of plural pairs of the sustaining electrodes, on a fluorescent material. And a sustaining electrode in the pair of sustaining electrodes disposed on the nearly flat surface of the first glass substrate provides a discharge gap region electrode, and a main surface discharge electrode, and an aperture disposed between the discharge gap region electrode and the main surface discharge electrode. And the main surface discharge electrode is composed of plural fine patterned wires and/or opening parts where electrodes are not formed.
According to a second aspect of the present invention, in the first aspect, the area of the main surface discharge electrode is 50% or less of the area of the region where the main surface discharge electrode is formed.
According to a third aspect of the present invention, in the first aspect, the area of the main surface discharge electrode is 30% or less of the area of the region where the main surface discharge electrode is formed.
According to a fourth aspect of the present invention, in the first aspect, the width of the fine patterned wire, of which the main surface discharge electrode is composed, is twice as narrow as or less of the value of the thickness of the dielectric layer for insulating the main surface discharge electrode from a discharge space.
According to a fifth aspect of the present invention, in the first aspect, the width of the discharge gap region electrode is 20% or less of the width of the sustaining electrode, disposed on the nearly flat surface of the first glass substrate, in the direction opposing the two sustaining electrodes each other in the pair of the sustaining electrodes.
According to a sixth aspect of the present invention, in the first aspect, the width of the discharge gap region electrode is 10% or less of the width of the sustaining electrode, disposed on the nearly flat surface of the first glass substrate, in the direction opposing the two sustaining electrodes each other in the pair of the sustaining electrodes.
According to a seventh aspect of the present invention, in the first aspect, the width of the aperture, which is disposed between the discharge gap region electrode and the main surface discharge electrode, is 10% or more of the width of the sustaining electrode in the direction opposing the two sustaining electrodes each other in the pair of the sustaining electrodes.
According to an eighth aspect of the present invention, in the first aspect, the width of the aperture, which is disposed between the discharge gap region electrode and the main surface discharge electrode, is 20% or more of the width of the sustaining electrode in the direction opposing the two sustaining electrodes each other in the pair of the sustaining electrodes.
According to a ninth aspect of the present invention, at least one of connecting electrodes for connecting the discharge gap region electrode and the main surface discharge electrode is disposed at the aperture that is disposed between the discharge gap region electrode and the main surface discharge electrode.
According to a tenth aspect of the present invention, in the ninth aspect, the area of the connecting electrodes is 20% or less of the area of the aperture.
According to an eleventh aspect of the present invention, in the first aspect, the thickness of the dielectric layer being nearly flat on the discharge gap region electrode is thinner than the thickness of the dielectric layer being nearly flat on the main surface discharge electrode.
According to a twelfth aspect of the present invention, in the first aspect, the sustaining electrode disposed on the nearly flat surface of the first glass substrate further provides a metal bus line positioned at the opposite side of the discharge gap region electrode and connected with both the discharge gap region electrode and the main surface discharge electrode, and a second aperture disposed between the main surface discharge electrode and the metal bus line. And the metal bus line makes wiring resistance of the sustaining electrode low.
According to a thirteenth aspect of the present invention, in the twelfth aspect, the width of the second aperture disposed between the main surface discharge electrode and the metal bus line is wider than the width of the aperture disposed between the discharge gap region electrode and the main surface discharge electrode.
According to a fourteenth aspect of the present invention, in the thirteenth aspect, a discharge is generated between the pair of the sustaining electrodes by applying voltages alternately to the pair of sustaining electrodes, and during a displaying discharge period by which the light emitting intensity of a light emitting display is controlled, the discharge is not spread in the region of the metal bus line beyond the second aperture.
According to a fifteenth aspect of the present invention, in the first aspect, the component of the gas generating ultraviolet light to irradiate to the fluorescent material is Xe, Kr, Ar, or nitrogen, and the partial pressure of the gas is 100 hPa or more.